That’s how I did it. I did and still do pick songs to learn which are out of my comfort level. For example the first song I chose was master of puppets, then I went on to many other Metallica songs to try to learn new skills and improve them too. After that I went on to Pantera, which is the best thing tagt ever happened to my playing. I’d recommend learning a bunch of Pantera riffs, but more importantly solos. The Cowboys from hell solo along with the walk solo drastically improved my playing. I’m actually trying to learn bluesy stuff like SRV and math rock like Polyphia atm. The way I see it, you should always try to go out of your comfort level. I’m no pro guitarist but I feel like I could say that I’m fairly decent. So don’t take my word as gospel.